1. Field of the Invention
The present invention relates to a camera system, and specifically relates to a camera system in which a varifocal lens is employed.
2. Description of the Background Art
A system controller of a camera has been conventionally designed to enter the halt state after completing a predetermined operation in order to save power. A start signal is thereafter sent to the controller, whereby the controller switches into the operative state to start the predetermined operation. In these types of conventional cameras, the start signal is generated due to an operation of an operation member provided in a camera body.
However, there may be situations where the controller in the camera body is required to perform a prompt operation in response to an operation on the lens side. For example, when a varifocal lens is adapted as a lens system in which a focal point position is shifted due to a zooming operation, it is indispensable to instantaneously correct the focal point position in response to the zooming operation to maintain the focused state at all times. If this correction is controlled by the system controller in the camera body, the controller must perform an instantaneous operation in response to the zooming operation on the lens side. Consequently, the conventional camera can not satisfy the above-described request because the start signal for the controller is designed to be generated only through the operation of the operation member in the camera body.